We acknowledge staff and instrumentation support from the Structural Biology Facility at Northwestern University. The support from the R.H. Lurie Comprehensive Cancer Center of Northwestern University and the Northwestern University Structural Biology Facilities is acknowledged. The Gatan K2 direct electron detector was purchased with funds provided by the Chicago Biomedical Consortium with support from the Searle Funds at The Chicago Community Trust. We also thank the following facilities at Northwestern University: the Keck Interdisciplinary Surface Science Facility, the Structural Biology Facility, the Biological Imaging Facility, the Center for Advanced Molecular Imaging, and the Analytical Bionanotechnology Equipment Core. This research was supported by the National Science Foundation grant 1453576, the National Institutes of Health Director&#39;s New Innovator Award 1DP2HL132390-01, the Center for Regenerative Nanomedicine Catalyst Award and the 2014 McCormick Catalyst Award. SDA was supported in part by NIH predoctoral Biotechnology Training Grant T32GM008449.

<ol>
	<li>Stano, A., Scott, E. A., Dane, K. Y., Swartz, M. A., Hubbell, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tunable+T+cell+immunity+towards+a+protein+antigen+using+polymersomes+vs.+solid-core+nanoparticles.">Tunable T cell immunity towards a protein antigen using polymersomes vs. solid-core nanoparticles.</a> Biomaterials. 34 (17), 4339-4346 (2013).</li><li>Discher, B. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymersomes:+tough+vesicles+made+from+diblock+copolymers.">Polymersomes: tough vesicles made from diblock copolymers.</a> Science. 284 (5417), 1143-1146 (1999).</li><li>Vasdekis, A. E., Scott, E. A., O'Neil, C. P., Psaltis, D., Hubbell, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+intracellular+delivery+based+on+optofluidic+polymersome+rupture.">Precision intracellular delivery based on optofluidic polymersome rupture.</a> ACS Nano. 6 (9), 7850-7857 (2012).</li><li>Yi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tailoring+Nanostructure+Morphology+for+Enhanced+Targeting+of+Dendritic+Cells+in+Atherosclerosis.">Tailoring Nanostructure Morphology for Enhanced Targeting of Dendritic Cells in Atherosclerosis.</a> ACS Nano. 10 (12), 11290-11303 (2016).</li><li>Shum, H. C., Kim, J. W., Weitz, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic+fabrication+of+monodisperse+biocompatible+and+biodegradable+polymersomes+with+controlled+permeability.">Microfluidic fabrication of monodisperse biocompatible and biodegradable polymersomes with controlled permeability.</a> Journal of the American Chemical Society. 130 (29), 9543-9549 (2008).</li><li>Pessi, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidics-assisted+engineering+of+polymeric+microcapsules+with+high+encapsulation+efficiency+for+protein+drug+delivery.">Microfluidics-assisted engineering of polymeric microcapsules with high encapsulation efficiency for protein drug delivery.</a> International Journal of Pharmaceutics. 472 (1-2), 82-87 (2014).</li><li>O'Neil, C. P., Suzuki, T., Demurtas, D., Finka, A., Hubbell, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+method+for+the+encapsulation+of+biomolecules+into+polymersomes+via+direct+hydration.">A novel method for the encapsulation of biomolecules into polymersomes via direct hydration.</a> Langmuir. 25 (16), 9025-9029 (2009).</li><li>Saad, W. S., Prud'homme, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Principles+of+nanoparticle+formation+by+flash+nanoprecipitation.">Principles of nanoparticle formation by flash nanoprecipitation.</a> Nano Today. 11 (2), 212-227 (2016).</li><li>Johnson, B. K., Prud'homme, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+for+rapid+self-assembly+of+block+copolymer+nanoparticles.">Mechanism for rapid self-assembly of block copolymer nanoparticles.</a> Physical Review Letters. 91 (11), 118302 (2003).</li><li>Han, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+confined+impingement+jets+mixer+for+flash+nanoprecipitation.">A simple confined impingement jets mixer for flash nanoprecipitation.</a> Journal of Pharmaceutical Sciences. 101 (10), 4018-4023 (2012).</li><li>Allen, S., Osorio, O., Liu, Y. G., Scott, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+assembly+and+loading+of+theranostic+polymersomes+via+multi-impingement+flash+nanoprecipitation.">Facile assembly and loading of theranostic polymersomes via multi-impingement flash nanoprecipitation.</a> Journal of Controlled Release. 262, 91-103 (2017).</li><li>Bobbala, S., Allen, S. D., Scott, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flash+nanoprecipitation+permits+versatile+assembly+and+loading+of+polymeric+bicontinuous+cubic+nanospheres.">Flash nanoprecipitation permits versatile assembly and loading of polymeric bicontinuous cubic nanospheres.</a> Nanoscale. 10 (11), 5078-5088 (2018).</li><li>Allen, S. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymersomes+scalably+fabricated+via+flash+nanoprecipitation+are+non-toxic+in+non-human+primates+and+associate+with+leukocytes+in+the+spleen+and+kidney+following+intravenous+administration.">Polymersomes scalably fabricated via flash nanoprecipitation are non-toxic in non-human primates and associate with leukocytes in the spleen and kidney following intravenous administration.</a> Nano Research. , (2018).</li><li>Karabin, N. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sustained+micellar+delivery+via+inducible+transitions+in+nanostructure+morphology.">Sustained micellar delivery via inducible transitions in nanostructure morphology.</a> Nature Communications. 9 (1), 624 (2018).</li><li>Mascoli, C. C., Weary, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Limulus+amebocyte+lysate+(LAL)+test+for+detecting+pyrogens+in+parenteral+injectable+products+and+medical+devices:+advantages+to+manufacturers+and+regulatory+officials.">Limulus amebocyte lysate (LAL) test for detecting pyrogens in parenteral injectable products and medical devices: advantages to manufacturers and regulatory officials.</a> Journal of the Parenteral Drug Association. 33 (2), 81-95 (1979).</li><li>Pustulka, K. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flash+nanoprecipitation:+particle+structure+and+stability.">Flash nanoprecipitation: particle structure and stability.</a> Molecular Pharmaceutics. 10 (11), 4367-4377 (2013).</li><li>Tang, C., Amin, D., Messersmith, P. B., Anthony, J. E., Prud'homme, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymer+directed+self-assembly+of+pH-responsive+antioxidant+nanoparticles.">Polymer directed self-assembly of pH-responsive antioxidant nanoparticles.</a> Langmuir. 31 (12), 3612-3620 (2015).</li><li>Gindy, M. E., Panagiotopoulos, A. Z., Prud'homme, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composite+block+copolymer+stabilized+nanoparticles:+simultaneous+encapsulation+of+organic+actives+and+inorganic+nanostructures.">Composite block copolymer stabilized nanoparticles: simultaneous encapsulation of organic actives and inorganic nanostructures.</a> Langmuir. 24 (1), 83-90 (2008).</li></ol>

The authors declare that they have no competing financial interests.

We have provided detailed instructions for the rapid fabrication of polymersomes using PEG17-bl-PPS35-SH as the diblock copolymer. Vesicular polymersomes are the primary aggregate morphology assembled at this ratio of hydrophilic PEG and hydrophobic PPS block molecular weight. When impinged multiple times, they have a diameter and polydispersity that matches polymersomes extruded through a 200 nm membrane after being formed via thin film hydration. This protocol thus eliminates the...

Nanocarriers allow for the controlled delivery of small and macromolecular cargo, including active entities that, if not encapsulated, would be either highly degradable and/or too hydrophobic for administration in vivo. Of the nanocarrier morphologies regularly fabricated, polymeric vesicles analogous to liposomes (also called polymersomes) offer the ability to simultaneously load hydrophilic and hydrophobic cargo1,2. Despite their promising advantages, polymersomes are still rare in clinical applications due, in part, to several key challenges in their manufacturing. For clinical use, polymersome formulations need to be made in large-scale, sterile, and consistent batches.
A number of techniques can be used to form polymersomes from a diblock copolymer, such as poly(ethylene glycol)-block-poly(propylene sulfide) (PEG-bl-PPS), that include solvent dispersion3, thin film rehydration1,4, microfluidics 5,6, and direct hydration7. Solvent dispersion involves long incubation times in the presence of organic solvents, which may denature some bioactive payloads, like proteins. Thin film rehydration does not offer control over the polydispersity of the formed polymersomes, often requiring expensive and time-consuming extrusion techniques to achieve acceptable monodispersity. Furthermore, both microfluids and direct hydration are difficult to scale up for larger production volumes. Of the different nanocarrier fabrication methods, flash nanoprecipitation (FNP) offers the ability to make large-scale and reproducible formulations8,9,10. While FNP was previously reserved for the formulation of solid-core nanoparticles, our lab has recently expanded the use of FNP to include the consistent formation of diverse PEG-bl-PPS nanostructure morphologies11,12, including polymersomes11 and bicontinuous nanospheres12. We found that FNP was capable of forming monodisperse formulations of polymersomes without the need for extrusion, resulting in superior polydispersity index values compared to non-extruded polymersomes formed by thin film rehydration and solvent dispersion11. Bicontinuous nanospheres, with their large hydrophobic domains, were not able to be formed by thin film rehydration, despite forming under a number of solvent conditions with FNP12.
Here, we provide a detailed description for the synthesis of the PEG-bl-PPS diblock copolymer used in polymersome formation, the confined impingement jets (CIJ) mixer used for FNP, the FNP protocol itself, and the implementation of an automated system to reduce user variability. Included is information on how to sterilize the system sufficiently to produce endotoxin-free formulations for use in vivo, and representative data concerning the characterization of polymersomes formed by FNP. With this information, readers with interest in utilizing polymersomes for in vitro and in vivo work will be able to fabricate their own sterile, monodisperse formulations. Readers with experience in nanocarrier formulations and with polymer synthesis expertise will be able to rapidly test their own polymer systems using FNP as a potential alternative to their current formulation techniques. Additionally, the protocols described herein may be used as educational tools for the formulation of nanocarriers in nanotechnology laboratory courses.

<table><tbody><tr><td>CanaKit Raspberry Pi 3 Ultimate Starter Kit - 32 GB Edition</td><td>CanaKit</td><td>UPC 682710991511</td><td></td></tr><tr><td>Linear Bearing Platform (Small) - 8mm Diameter</td><td>Adafruit</td><td>1179</td><td></td></tr><tr><td>Linear Motion 8 mm Shaft, 330 mm Length, Chrome Plated, Case Hardened, Metric</td><td>VXB</td><td>kit11868</td><td></td></tr><tr><td>Linear Rail Shaft Guide/Support - 8 mm Diameter</td><td>Adafruit</td><td>1182</td><td></td></tr><tr><td>Manual-Position Precision Slide 4.5&quot; Stroke, 15 lb load capacity</td><td>McMaster-Carr</td><td>5236A16</td><td></td></tr><tr><td>MTPM-P10-1JK43 Iron Horse DC motor</td><td>Iron Horse</td><td>MTPM-P10-1JK43</td><td></td></tr><tr><td>Official Raspberry Pi Foundation 7&quot; Touchscreen LCD Display</td><td>Raspberry Pi</td><td>B0153R2A9I (ASIN)</td><td></td></tr><tr><td>PicoBorg Reverse - Advanced motor control for Raspberry Pi</td><td>PiBorg</td><td>BURN-0011</td><td></td></tr><tr><td>Pololu Carrier with Sharp GP2Y0D810Z0F Digital Distance Sensor 10cm</td><td>Pololu</td><td>1134</td><td></td></tr><tr><td>Ruland PSR16-5-4-A Set Screw Beam Coupling, Polished Aluminum, Inch, 5/16&quot; Bore A Diameter, 1/4&quot; Bore B Diameter, 1&quot; OD, 1-1/4&quot; Length, 44 lb-in Nominal Torque</td><td>Ruland</td><td>PSR16-5-4-A</td><td></td></tr><tr><td>Polyethylene glycol monomethyl ether</td><td>Sigma Aldrich</td><td>202495</td><td></td></tr><tr><td>Methanesulfonyl chloride</td><td>Sigma Aldrich</td><td>471259</td><td></td></tr><tr><td>Toluene</td><td>Sigma Aldrich</td><td>179418</td><td></td></tr><tr><td>Toluene, Anhydrous</td><td>Sigma Aldrich</td><td>244511</td><td></td></tr><tr><td>Triethylamine</td><td>Sigma Aldrich</td><td>T0886</td><td></td></tr><tr><td>Celite 545 (Diatomaceous Earth)</td><td>Sigma Aldrich</td><td>419931</td><td></td></tr><tr><td>Dichloromethane</td><td>Sigma Aldrich</td><td>320269</td><td></td></tr><tr><td>Diethyl ether</td><td>Sigma Aldrich</td><td>296082</td><td></td></tr><tr><td>N,N-Dimethylformamide, anhydrous</td><td>Sigma Aldrich</td><td>227056</td><td></td></tr><tr><td>Potassium carbonate</td><td>Sigma Aldrich</td><td>791776</td><td></td></tr><tr><td>Thioacetic acid</td><td>Sigma Aldrich</td><td>T30805</td><td></td></tr><tr><td>Tetrahydrofuran</td><td>Sigma Aldrich</td><td>360589</td><td></td></tr><tr><td>Aluminum oxide, neutral, activated, Brockmann I</td><td>Sigma Aldrich</td><td>199974</td><td></td></tr><tr><td>Sodium methoxide solution, 0.5 M in methanol</td><td>Sigma Aldrich</td><td>403067</td><td></td></tr><tr><td>Propylene sulfide</td><td>Sigma Aldrich</td><td>P53209</td><td></td></tr><tr><td>Acetic acid</td><td>Sigma Aldrich</td><td>A6283</td><td></td></tr><tr><td>Methanol</td><td>Sigma Aldrich</td><td>320390</td><td></td></tr><tr><td>Sodium hydroxide solution 1.0 N</td><td>Sigma Aldrich</td><td>S2770</td><td></td></tr><tr><td>Endotoxin-free water</td><td>GE Healthcare Life Sciences</td><td>SH30529.01</td><td></td></tr><tr><td>Paper pH strips</td><td>Fisher Scientific</td><td>13-640-508</td><td></td></tr><tr><td>Endotoxin-free Dulbecco&#039;s PBS</td><td>Sigma Aldrich</td><td>TMS-012</td><td></td></tr><tr><td>Borosilicate glass scintillation vials</td><td>Fisher Scientific</td><td>03-337-4</td><td></td></tr><tr><td>1 mL all-plastic syringe</td><td>Thermo Scientific</td><td>S75101</td><td></td></tr><tr><td>Sepharose CL-6B</td><td>Sigma Aldrich</td><td>CL6B200</td><td></td></tr><tr><td>Liquid chromatography column</td><td>Sigma Aldrich</td><td>C4169</td><td></td></tr><tr><td>CIJ mixer, HDPE</td><td>Custom</td><td></td><td></td></tr><tr><td>Triton X-100</td><td>Sigma Aldrich</td><td>X100</td><td></td></tr><tr><td>Hydrogen peroxide solution</td><td>Sigma Aldrich</td><td>216763</td><td></td></tr><tr><td>HEK-Blue hTLR4</td><td>InvivoGen</td><td>hkb-htlr4</td><td></td></tr><tr><td>RAW-Blue Cells</td><td>InvivoGen</td><td>raw-sp</td><td></td></tr><tr><td>QUANTI-Blue</td><td>InvivoGen</td><td>rep-qb1</td><td></td></tr><tr><td>PYROGENT Gel Clot LAL Assays</td><td>Lonza</td><td>N183-125</td><td></td></tr></tbody></table>

rapid, scalable assembly and loading of bioactive proteins and immunostimulants into diverse synthetic nanocarriers via flash nanoprecipitation

Nanomaterials present a wide range of options to customize the controlled delivery of single and combined molecular payloads for therapeutic and imaging applications. This increased specificity can have significant clinical implications, including decreased side effects and lower dosages with higher potency. Furthermore, the in situ targeting and controlled modulation of specific cell subsets can enhance in vitro and in vivo investigations of basic biological phenomena and probe cell function. Unfortunately, the required expertise in nanoscale science, chemistry and engineering often prohibit laboratories without experience in these fields from fabricating and customizing nanomaterials as tools for their investigations or vehicles for their therapeutic strategies. Here, we provide protocols for the synthesis and scalable assembly of a versatile non-toxic block copolymer system amenable to the facile formation and loading of nanoscale vehicles for biomedical applications. Flash nanoprecipitation is presented as a methodology for rapid fabrication of diverse nanocarriers from poly(ethylene glycol)-bl-poly(propylene sulfide) copolymers. These protocols will allow laboratories with a wide range of expertise and resources to easily and reproducibly fabricate advanced nanocarrier delivery systems for their applications. The design and construction of an automated instrument that employs a high-speed syringe pump to facilitate the flash nanoprecipitation process and to allow enhanced control over the homogeneity, size, morphology and loading of polymersome nanocarriers is described.

Here, we have presented a simple protocol for the formulation of nanocarriers capable of loading hydrophilic and hydrophobic cargo that are safe for in vivo mouse and non-human primate administration11,13. We have also included a detailed protocol for the synthesis of the polymer used in our representative results, along with a description for the fabrication of a custom instrument for the mechanically-controlled impingem...

Watch this Scientific Journal Video about Rapid, Scalable Assembly and Loading of Bioactive Proteins and Immunostimulants into Diverse Synthetic Nanocarriers Via Flash Nanoprecipitation at JoVE.com

Rapid, Scalable Assembly and Loading of Bioactive Proteins and Immunostimulants into Diverse Synthetic Nanocarriers Via Flash Nanoprecipitation

Nanomaterials provide versatile mechanisms of controlled therapeutic delivery for both basic science and translational applications, but their fabrication often requires expertise that is unavailable in most biomedical laboratories. Here, we present protocols for the scalable fabrication and therapeutic loading of diverse self-assembled nanocarriers using flash nanoprecipitation.

Nanomaterials present a wide range of options to customize the controlled delivery of single and combined molecular payloads for therapeutic and imaging ...

rapid-scalable-assembly-loading-bioactive-proteins-immunostimulants

Research

JoVE Journal

Bioengineering

7.8K Views.  Northwestern University. Nanomaterialen bieden veelzijdige mechanismen van gecontroleerde therapeutische aflevering voor zowel basiswetenschap en translationeel toepassingen, maar hun fabricage vaak vereist expertise die niet beschikbaar is in de meest biomedische laboratoria. Hier presenteren we protocollen voor het schaalbare fabricage en therapeutische laden van uiteenlopende zelf gemonteerd nanocarriers met behulp van flash nanoprecipitation.

Video: Rapid, Scalable Assembly and Loading of Bioactive Proteins and Immunostimulants into Diverse Synthetic Nanocarriers Via Flash Nanoprecipitation

High-throughput Synthesis of Carbohydrates and Functionalization of Polyanhydride Nanoparticles

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design efficacious vaccines carriers. Nanoparticle-based platforms can prolong the persistence of vaccine antigens, which could improve vaccine immunogenicity1. Several biodegradable polymers have been studied as vaccine delivery vehicles1; in particular, polyanhydride particles have demonstrated the ability to provide sustained release of stable protein antigens and to activate antigen presenting cells and modulate immune responses2-12.
The molecular design of these vaccine carriers needs to integrate the rational selection of polymer properties as well as the incorporation of appropriate targeting agents. High throughput automated fabrication of targeting ligands and functionalized particles is a powerful tool that will enhance the ability to study a wide range of properties and will lead to the design of reproducible vaccine delivery devices.
The addition of targeting ligands capable of being recognized by specific receptors on immune cells has been shown to modulate and tailor immune responses10,11,13 C-type lectin receptors (CLRs) are pattern recognition receptors (PRRs) that recognize carbohydrates present on the surface of pathogens. The stimulation of immune cells via CLRs allows for enhanced internalization of antigen and subsequent presentation for further T cell activation14,15. Therefore, carbohydrate molecules play an important role in the study of immune responses; however, the use of these biomolecules often suffers from the lack of availability of structurally well-defined and pure carbohydrates. An automation platform based on iterative solution-phase reactions can enable rapid and controlled synthesis of these synthetically challenging molecules using significantly lower building block quantities than traditional solid-phase methods16,17.
Herein we report a protocol for the automated solution-phase synthesis of oligosaccharides such as mannose-based targeting ligands with fluorous solid-phase extraction for intermediate purification. After development of automated methods to make the carbohydrate-based targeting agent, we describe methods for their attachment on the surface of polyanhydride nanoparticles employing an automated robotic set up operated by LabVIEW as previously described10. Surface functionalization with carbohydrates has shown efficacy in targeting CLRs10,11 and increasing the throughput of the fabrication method to unearth the complexities associated with a multi-parametric system will be of great value (Figure 1a).

In this article, a high throughput method is presented for the synthesis of oligosaccharides and their attachment to the surface of polyanhydride nanoparticles for further use in targeting specific receptors on antigen presenting cells.

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design ...

Intra-lymph Node Injection of Biodegradable Polymer Particles

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these foreign molecules to T and B lymphocytes. Lymph nodes have thus become critical targets for new vaccines and immunotherapies. A recent strategy for targeting these tissues is direct lymph node injection of soluble vaccine components, and clinical trials involving this technique have been promising. Several biomaterial strategies have also been investigated to improve lymph node targeting, for example, tuning particle size for optimal drainage of biomaterial vaccine particles. In this paper we present a new method that combines direct lymph node injection with biodegradable polymer particles that can be laden with antigen, adjuvant, or other vaccine components. In this method polymeric microparticles or nanoparticles are synthesized by a modified double emulsion protocol incorporating lipid stabilizers. Particle properties (e.g.&#160;size, cargo loading) are confirmed by laser diffraction and fluorescent microscopy, respectively. Mouse lymph nodes are then identified by peripheral injection of a nontoxic tracer dye that allows visualization of the target injection site and subsequent deposition of polymer particles in lymph nodes. This technique allows direct control over the doses and combinations of biomaterials and vaccine components delivered to lymph nodes and could be harnessed in the development of new biomaterial-based vaccines.

Lymph nodes are the immunological tissues that orchestrate immune response and are a critical target for vaccines. Biomaterials have been employed to better target lymph nodes and to control delivery of antigens or adjuvants. This paper describes a technique combining these ideas to inject biocompatible polymer particles into lymph nodes.

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these ...

Fabrication of Spherical and Worm-shaped Micellar Nanocrystals by Combining Electrospray, Self-assembly, and Solvent-based Structure Control

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of fabricating micellar nanocrystals based on combining top-down electrospray, bottom-up self-assembly, and solvent-based structure control. This method involves first using electrospray to generate uniform ultrafine liquid droplets, each of which functions as a micro-reactor in which self-assembly reaction occurs forming micellar nanocrystals, with the structures (micelle shape and nanocrystal encapsulation) controlled by the organic solvent used. This method is largely continuous and produces high quality micellar nanocrystal products with an inexpensive structure control approach. By using a water-miscible organic solvent tetrahydrofuran (THF), worm-shaped micellar nanocrystals can be produced due to solvent-induced/facilitated micelle fusion. Compared with the common spherical micellar nanocrystals, worm-shaped micellar nanocrystals can offer minimized non-specific cellular uptake, thus enhancing biological targeting. By co-encapsulating multiple nanocrystals into each micelle, multifunctional or synergistic effects can be achieved. Current limitations of this fabrication method, which will be part of the future work, primarily include imperfect encapsulation in the micellar nanocrystal product and the incompletely continuous nature of the process.

The present work describes a method to fabricate micellar nanocrystals, an emerging major class of nanobiomaterials. This method combines top-down electrospray, bottom-up self-assembly, and solvent-based structure control. The fabrication method is largely continuous, can produce high quality products, and possesses an inexpensive means of structure control.

Micellar nanocrystals (micelles with encapsulated nanocrystals) have become an emerging major class of nanobiomaterials. We describe a method of ...

Chemistry

Whole-animal Imaging and Flow Cytometric Techniques for Analysis of Antigen-specific CD8+ T Cell Responses after Nanoparticle Vaccination

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various nanoparticle systems have been engineered to mimic features of pathogens to improve antigen delivery to draining lymph nodes and increase antigen uptake by antigen-presenting cells, leading to new vaccine formulations optimized for induction of antigen-specific CD8+ T cell responses. In this article, we describe the synthesis of a &#8220;pathogen-mimicking&#8221; nanoparticle system, termed interbilayer-crosslinked multilamellar vesicles (ICMVs) that can serve as an effective vaccine carrier for co-delivery of subunit antigens and immunostimulatory agents and elicitation of potent cytotoxic CD8+ T lymphocyte (CTL) responses. We describe methods for characterizing hydrodynamic size and surface charge of vaccine nanoparticles with dynamic light scattering and zeta potential analyzer and present a confocal microscopy-based procedure to analyze nanoparticle-mediated antigen delivery to draining lymph nodes. Furthermore, we show a new bioluminescence whole-animal imaging technique utilizing adoptive transfer of luciferase-expressing, antigen-specific CD8+ T cells into recipient mice, followed by nanoparticle vaccination, which permits non-invasive interrogation of expansion and trafficking patterns of CTLs in real time. We also describe tetramer staining and flow cytometric analysis of peripheral blood mononuclear cells for longitudinal quantification of endogenous T cell responses in mice vaccinated with nanoparticles.

We describe whole-animal imaging and flow cytometry-based techniques for monitoring expansion of antigen-specific CD8+ T cells in response to immunization with nanoparticles in a murine model of vaccination.

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various ...

Immunology and Infection

Directed Assembly of Elastin-like Proteins into defined Supramolecular Structures and Cargo Encapsulation In Vitro

Tailored proteinaceous building blocks are versatile candidates for the assembly of supramolecular structures such as minimal cells, drug delivery vehicles and enzyme scaffolds. Due to their biocompatibility and tunability on the genetic level, Elastin-like proteins (ELP) are ideal building blocks for biotechnological and biomedical applications. Nevertheless, the assembly of protein based supramolecular structures with distinct physiochemical properties and good encapsulation potential remains challenging.
Here we provide two efficient protocols for guided self-assembly of amphiphilic ELPs into supramolecular protein architectures such as spherical coacervates, fibers and stable vesicles. The presented assembly protocols generate Protein Membrane-Based Compartments (PMBCs) based on ELPs with adaptable physicochemical properties. PMBCs demonstrate phase separation behavior and reveal method dependent membrane fusion and are able to encapsulate chemically diverse fluorescent cargo molecules. The resulting PMBCs have a high application potential as a drug formulation and delivery platform, artificial cell, and compartmentalized reaction space.

At the interface of organic and aqueous solvents, tailored amphiphilic elastin-like proteins assemble into complex supramolecular structures such as vesicles, fibers and coacervates triggered by environmental parameters. The described assembly protocols yield Protein Membrane-Based Compartments (PMBCs) with tunable properties, enabling the encapsulation of various cargo.

Tailored proteinaceous building blocks are versatile candidates for the assembly of supramolecular structures such as minimal cells, drug delivery ...

Preparation and Characterization of Novel HDL-mimicking Nanoparticles for Nerve Growth Factor Encapsulation

The objective of this article is to introduce preparation and characterization methods for nerve growth factor (NGF)-loaded, high-density, lipoprotein (HDL)-mimicking nanoparticles (NPs). HDLs are endogenous NPs and have been explored as vehicles for the delivery of therapeutic agents. Various methods have been developed to prepare HDL-mimicking NPs. However, they are generally complicated, time consuming, and difficult for industrial scale-up. In this study, one-step homogenization was used to mix the excipients and form the prototype NPs. NGF is a water-soluble protein of 26 kDa. To facilitate the encapsulation of NGF into the lipid environment of HDL-mimicking NPs, protamine USP was used to form an ion-pair complex with NGF to neutralize the charges on the NGF surface. The NGF/protamine complex was then introduced into the prototype NPs. Apolipoprotein A-I was finally coated on the surface of the NPs. NGF HDL-mimicking NPs showed preferable properties in terms of particle size, size distribution, entrapment efficiency, in vitro release, bioactivity, and biodistribution. With the careful design and exploration of homogenization in HDL-mimicking NPs, the procedure was greatly simplified, and the NPs were made scalable. Moreover, various challenges, such as separating unloaded NGF from the NPs, conducting reliable in vitro release studies, and measuring the bioactivity of the NPs, were overcome.

Simple homogenization was used to prepare novel, high-density, lipoprotein-mimicking nanoparticles to encapsulate nerve growth factor. Challenges, detailed protocols for nanoparticle preparation, in vitro characterization, and in vivo studies are described in this article.

The objective of this article is to introduce preparation and characterization methods for nerve growth factor (NGF)-loaded, high-density, lipoprotein ...

Synthesis of Stimuli-responsive Nanogels using Aqueous One-step Crosslinking and Co-nanopolymerization

Nanogels consisting of crosslinked-polymeric nanoparticles have been developed for the delivery of numerous chemical and biological therapeutics, owing to their versatile bottom-up synthesis and biocompatibility. While various methods have been employed for nanogel synthesis to date, very few have achieved it without the use of harsh organic solvents or high temperatures that can damage the integrity of the biological payload. In contrast, the methodology presented here accomplishes the synthesis of sub-100 nm sized, protein-loaded nanogels using mild reaction conditions. Here, we present a method for the non-covalent encapsulation of protein-based payloads within nano-gels that were synthesized using an aqueous-based, single-step, crosslinking copolymerization technique. In this technique, we initially electrostatically bind a protein-based payload to a cationic quaternary ammonium monomer and simultaneously cross-link and co-polymerize it using ammonium persulfate and N,N,N&#39;,N&#39;-tetramethylethylenediamine to form nanogels that entrap the protein payload. The size and polydispersity index of the nanogels is determined using dynamic light scattering (DLS), while the surface morphology is assessed by transmission electron microscopy (TEM). The mass of protein entrapped within nanogels is determined by calculating the encapsulation efficiency. Furthermore, the controlled-release ability of the nanogels via the gradual degradation of redox-responsive structural elements is also assessed in bioreduction assays. We provide examples of nanoparticle optimization data to demonstrate all caveats of nanogel synthesis and characterization using this technique. In general, uniformly sized nanogels were obtained with an average size of 57 nm and a polydispersity index value of 0.093. A high encapsulation efficiency of 76% was achieved. Furthermore, the nanogels exhibited controlled release of up to 86% of the encapsulated protein by gradual degradation of novel redox-responsive components in the presence of glutathione over 48 h.

Nanogels are an excellent and versatile nanoparticle platform for the delivery of biologics. Stimuli-responsive poly(ethylene) glycol-based polymeric nano-gels, capable of encapsulating protein-based payloads, were synthesized using a one-step cross-linking co-nanopolymerization strategy in aqueous conditions. The optimal fabrication and characterization of these novel nanoparticles are presented here.

Nanogels consisting of crosslinked-polymeric nanoparticles have been developed for the delivery of numerous chemical and biological therapeutics, owing to ...

Flash NanoPrecipitation for the Encapsulation of Hydrophobic and Hydrophilic Compounds in Polymeric Nanoparticles

The formulation of a therapeutic compound into nanoparticles (NPs) can impart unique properties. For poorly water-soluble drugs, NP formulations can improve bioavailability and modify drug distribution within the body. For hydrophilic drugs like peptides or proteins, encapsulation within NPs can also provide protection from natural clearance mechanisms. There are few techniques for the production of polymeric NPs that are scalable. Flash NanoPrecipitation (FNP) is a process that uses engineered mixing geometries to produce NPs with narrow size distributions and tunable sizes between 30 and 400 nm. This protocol provides instructions on the laboratory-scale production of core-shell polymeric nanoparticles of a target size using FNP. The protocol can be implemented to encapsulate either hydrophilic or hydrophobic compounds with only minor modifications. The technique can be readily employed in the laboratory at milligram scale to screen formulations. Lead hits can directly be scaled up to gram- and kilogram-scale. As a continuous process, scale-up involves longer mixing process run time rather than translation to new process vessels. NPs produced by FNP are highly loaded with therapeutic, feature a dense stabilizing polymer brush, and have a size reproducibility of &#177; 6%.

Flash NanoPrecipitation (FNP) is a scalable approach to produce polymeric core-shell nanoparticles. Lab-scale formulations for the encapsulation of hydrophobic or hydrophilic therapeutics are described.

The formulation of a therapeutic compound into nanoparticles (NPs) can impart unique properties. For poorly water-soluble drugs, NP formulations can ...

Formulating and Characterizing Lipid Nanoparticles for Gene Delivery using a Microfluidic Mixing Platform

Lipid-based drug carriers have been used for clinically and commercially available delivery systems due to their small size, biocompatibility, and high encapsulation efficiency. Use of lipid nanoparticles (LNPs) to encapsulate nucleic acids is advantageous to protect the RNA or DNA from degradation, while also promoting cellular uptake. LNPs often contain multiple lipid components including an ionizable lipid, helper lipid, cholesterol, and polyethylene glycol (PEG) conjugated lipid. LNPs can readily encapsulate nucleic acids due to the ionizable lipid presence, which at low pH is cationic and allows for complexation with negatively charged RNA or DNA. Here LNPs are formed by encapsulating messenger RNA (mRNA) or plasmid DNA (pDNA) using rapid mixing of the lipid components in an organic phase and the nucleic acid component in an aqueous phase. This mixing is performed using a precise microfluidic mixing platform, allowing for nanoparticle self-assembly while maintaining laminar flow. The hydrodynamic size and polydispersity are measured using dynamic light scattering (DLS). The effective surface charge on the LNP is determined by measuring the zeta potential. The encapsulation efficiency is characterized using a fluorescent dye to quantify entrapped nucleic acid. Representative results demonstrate the reproducibility of this method and the influence that different formulation and process parameters have on the developed LNPs.

Lipid nanoparticles are developed using a microfluidic mixing platform approach for mRNA and DNA encapsulation.

Lipid-based drug carriers have been used for clinically and commercially available delivery systems due to their small size, biocompatibility, and high ...

Synthesis and Characterization of mRNA-Loaded Poly(Beta Aminoesters) Nanoparticles for Vaccination Purposes

Vaccination has been one of the major successes of modern society and is indispensable in controlling and preventing disease. Traditional vaccines were composed of entire or fractions of the infectious agent. However, challenges remain, and new vaccine technologies are mandatory. In this context, the use of mRNA for immunizing purposes has shown an enhanced performance, as demonstrated by the speedy approval of two mRNA vaccines preventing SARS-CoV-2 infection. Beyond success in preventing viral infections, mRNA vaccines can also be used for therapeutic cancer applications.
Nevertheless, the instability of mRNA and its fast clearance from the body due to the presence of nucleases makes its naked delivery not possible. In this context, nanomedicines, and specifically polymeric nanoparticles, are critical mRNA delivery systems. Thus, the aim of this article is to describe the protocol for the formulation and test of an mRNA vaccine candidate based on the proprietary polymeric nanoparticles. The synthesis and chemical characterization of the poly(beta aminoesters) polymers used, their complexation with mRNA to form nanoparticles, and their lyophilization methodology will be discussed here. This is a crucial step for decreasing storage and distribution costs. Finally, the required tests to demonstrate their capacity to in vitro transfect and mature model dendritic cells will be indicated. This protocol will benefit the scientific community working on vaccination because of its high versatility that enables these vaccines to prevent or cure a wide variety of diseases.

Synthesis and Characterization of mRNA-Loaded PolyBeta Aminoesters Nanoparticles for Vaccination Purposes

Here, a simple protocol is presented for producing mRNA nanoparticles based on poly(beta aminoester) polymers, easy to be tailored by changing the encapsulated mRNA. The workflow for synthesizing the polymers, the nanoparticles, and their in vitro essential characterization are also described. A proof-of-concept regarding immunization is also added.

Vaccination has been one of the major successes of modern society and is indispensable in controlling and preventing disease. Traditional vaccines were ...

Rapid, Scalable Assembly and Loading of Bioactive Proteins and Immunostimulants into Diverse Synthetic Nanocarriers Via Flash Nanoprecipitation

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